A cost effective method of extending and improving a telephone service by utilizing existing infrastructure

In developing countries a large portion of the population tends to live in rural areas, where the cost of the link between the exchange and the subscriber is a high percentage of the total cost of providing the telephone service. Maintenance in rural areas is also very expensive because of geographically widespread equipment, harsh environmental conditions and theft or vandalism of routes. The authors describes the Magnolia system, which addresses these problems with a cost-effective, shared line (or channel), manual or automatic telephone system. It uses modern technology to implement a robust, in-band signaling system and incorporates features which largely overcome problems traditionally associated with shared line systems, while providing sophisticated facilities to both user and service provider. Many rural areas already have an open-wide or FDM (frequency division multiplexing) carrier infrastructure. This system allows the telephone service to be upgraded to a more modern standard, including automation of previously manual systems and connection to any type of telephone exchange via conventional two-wire circuits